Jackson Pollock. Number 1A, 1948. 1948. Oil and enamel paint on canvas, 68” x 8’8.” On view at MoMA in a recent acquisitions exhibition in 1950

Readers who have been following the blog will recognize a pattern in our approach to conservation treatment of Number 1A, 1948, the final of three Jackson Pollock paintings that have been the focus of our 18-month project. While each painting brings a unique set of materials and history, conservators generally follow a systematic logic to identify and prioritize preservation problems requiring attention. Our strategy in undertaking this treatment, therefore, echoes those of our two prior paintings. First, we gathered data, both archival and observational. We looked closely at the painting, under magnification and various lighting conditions, and compared what we saw to existing photographs and textual descriptions. We consulted conservation, curatorial, and scientific colleagues to clarify questions and gain a broader perspective in assessing 1A’s current state of preservation, the degradation mechanisms at work, and the altered aesthetic impact caused by the painting’s prior damage. As with Echo and One, this gathered information was essential in informing our treatment plan. We recorded our observations and photographically documented Number 1A at each stage of our work.

Our initial treatment steps addressed basic maintenance of the painting. As the painting had not been cleaned beyond light dusting since the 1970s, decades of airborne particles had settled into a layer of surface dirt and grime across both canvas and paint surfaces. We used small, stiff brushes to dislodge dust from the canvas, and we cleaned the paint surface using an aqueous solution gently brushed on and around the crevices of Pollock’s impasto.

Decades of dust and grime had settled to form a layer on delicate impasto surfaces

Cleaning the surface with an aqueous solution reduced the deposited dirt

With dust removed, three points emerged as primary aims of our treatment: diminishing the uneven discoloration across the exposed areas of canvas, filling the numerous losses to the paint layer, and correcting the bulkiness of the current stretcher, which had been replaced after the 1958 fire.

Blotchy staining disfigured areas of exposed canvas. Also note the disrupted skeins of yellow and white paint. Tenuously held bits of paint, made brittle by heat exposure, had been lost over the years

Dealing with the uneven discolored canvas proved to be a challenge, as some areas of staining were easily reduced while others remained stubbornly discolored. Similar to Echo and One, we reduced some of the yellowing of 1A’s canvas using damp blotters to wick soluble discolored materials into the blotter. Other areas of patchy darkening, however, persisted, and, after extensive testing, we chose to tone these areas using a light application of dry pigment and pastels—essentially retouching the stains. As with most conservation treatments, we focused on problematic areas with the aesthetic whole of the painting in mind, stepping back again and again to assess the effects of our work on the composition.

A combination of cleaning and retouching yield a more even tonality to the canvas as a whole

Though the stains aren’t completely gone, we’ve been successful in reducing their visual impact using re-treatable practices.

Tackling the losses to the paint layer proved to be more straightforward. We tested a variety of acrylic impasto gels, painting them out onto Mylar and canvas boards to assess their working properties.

Impasto mock-ups

We selected a flexible, easily carvable material, and extruded it, using a syringe, onto Mylar. After our “faux impasto” had dried, we carved it to size,

The flexible gel is easily carvable. The fill is just above the cotton swab in the image

painted it to match the appropriate hue, and placed it using a few tiny drops of viscous adhesive. The result is a seemingly continuous tendril of oil paint.

After treatment: The impasto has been retouched to match the original on either side of it. The fill spans the loss and can easily be removed

Finally, we chose to replace Number 1A’s stretcher. The stretcher to which the painting had been mounted after the fire is double the depth (1.5″) of Pollock’s original (.75″) based on the location of the original tack holes on the edge of the canvas. Moreover, a second, supporting canvas between the original and the stretcher bars prevented access to the painting’s reverse. To treat the canvas staining, we needed to work from the front and back of the painting, which required unstretching 1A. We took this opportunity to design a new stretcher for the work—one that would support the fragile paint layer, allow access to the reverse, and better reflect Pollock’s original dimensions.

The reverse of Number 1A, mounted to its new stretcher with insert panels

The resulting support includes a removable insert panel, protecting the canvas from vibration and movement that would lead to further paint loss.

Re-stretched, the visual change rendered by 1A’s restoration is at once subtle and wholly transforming. The viewer’s eye no longer lingers on disfigurement due to age or damage. Rather, one simply encounters Pollock’s composition in its entirety, refreshed and restored.

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